The concept of "Ideal Body Weight" (IBW) is a guideline used to estimate a healthy weight range for an individual based on their height and gender. It's important to note that IBW is a theoretical value and doesn't account for individual body composition (like muscle mass vs. fat mass), bone density, or overall health status. Therefore, it should be used as a reference point rather than a strict target.
How Ideal Body Weight is Calculated
Several formulas exist to estimate ideal body weight. Two commonly used methods, the Devine formula and the Robinson formula, are adapted for this calculator. These formulas provide slightly different estimates, hence we present a range.
1. Devine Formula:
For Men: 50 kg + 2.3 kg for each inch over 5 feet.
For Women: 45.5 kg + 2.3 kg for each inch over 5 feet.
2. Robinson Formula:
For Men: 52 kg + 1.9 kg for each inch over 5 feet.
For Women: 49 kg + 1.7 kg for each inch over 5 feet.
The Calculation Process
This calculator first converts your entered height into total inches. Then, it calculates your total inches over 5 feet (60 inches). Using the appropriate gender-based formula (Devine and Robinson), it computes two values. The final result presented is the range between these two calculated ideal body weights.
Example Calculation:
Let's consider a man who is 5 feet 10 inches tall (which is 70 inches).
Devine Formula (Male): 50 kg + (2.3 kg/inch * 10 inches) = 50 kg + 23 kg = 73 kg.
Robinson Formula (Male): 52 kg + (1.9 kg/inch * 10 inches) = 52 kg + 19 kg = 71 kg.
The ideal body weight range for this individual would be approximately 71 kg to 73 kg.
Who Can Benefit from This Calculator?
This calculator can be a useful tool for:
Individuals seeking a general understanding of a healthy weight target for their height and gender.
Health and fitness enthusiasts looking for reference points in their wellness journey.
Healthcare professionals who may use it as a preliminary guideline in patient assessments.
Important Considerations
Remember, this calculator provides an estimate. Factors like muscle mass, body fat percentage, age, and individual body frame can significantly influence what is a truly healthy weight for you. Always consult with a healthcare provider or a registered dietitian for personalized advice regarding your weight and overall health.
function calculateIdealBodyWeight() {
var gender = document.getElementById("gender").value;
var heightFeet = parseFloat(document.getElementById("heightFeet").value);
var heightInches = parseFloat(document.getElementById("heightInches").value);
var resultElement = document.getElementById("idealWeightResult");
resultElement.innerHTML = "–"; // Clear previous result
if (isNaN(heightFeet) || isNaN(heightInches)) {
alert("Please enter valid numbers for height.");
return;
}
if (heightFeet < 1 || heightInches 11) {
alert("Please enter a valid height.");
return;
}
var totalInches = (heightFeet * 12) + heightInches;
var inchesOver5Feet = totalInches – 60;
if (inchesOver5Feet < 0) {
inchesOver5Feet = 0; // Handle cases where height is less than 5 feet
}
var idealWeightKg_Devine;
var idealWeightKg_Robinson;
if (gender === "male") {
idealWeightKg_Devine = 50 + (2.3 * inchesOver5Feet);
idealWeightKg_Robinson = 52 + (1.9 * inchesOver5Feet);
} else { // Female
idealWeightKg_Devine = 45.5 + (2.3 * inchesOver5Feet);
idealWeightKg_Robinson = 49 + (1.7 * inchesOver5Feet);
}
// Ensure results are not negative (though unlikely with valid inputs)
idealWeightKg_Devine = Math.max(0, idealWeightKg_Devine);
idealWeightKg_Robinson = Math.max(0, idealWeightKg_Robinson);
// Determine the range
var lowerBound = Math.min(idealWeightKg_Devine, idealWeightKg_Robinson);
var upperBound = Math.max(idealWeightKg_Devine, idealWeightKg_Robinson);
// Format the output to one decimal place
var formattedLowerBound = lowerBound.toFixed(1);
var formattedUpperBound = upperBound.toFixed(1);
resultElement.innerHTML = formattedLowerBound + " kg – " + formattedUpperBound + " kg";
}